From the publisher's website:
At last, the eagerly anticipated guide to the Explorer's Society is here! From the depths of ancient ruins to the far reaches of the sea, the Explorers seek out all that which is hidden. They brave untold dangers - Syrneth traps, fearsome monsters, and horrors unheard - to uncover the mysteries of their world. Join their ranks... and learn what wonders lie beyond the horizon. Includes complete details on Theah's most prominent secret society: history, organization, and modus operandi, as well as rules for running Explorer campaigns in any gaming world. Fully compatible "hybrid" rules, suitable for BOTH d20 System play and 7th Sea's classic roll-and-keep system.